Amino Acids Flashcards
How many standard amino acids are there?
20
Describe the structure of a standard amino acid
Central carbon (alpha) bonded to a hydrogen, an R (side chain) group, a carboxyl group and an amino group
Which is the only standard amino acid that is attached to more than the central carbon?
Proline.
Attached to the central carbon and the nitrogen on the amino group
How many classes of amino acids are there?
4 classes:
Hydrophobic
Hydrophilic
Acidic
Basic
What is the name of the smallest amino acid?
Glycine
What are the two types of hydrocarbon side chains?
- Aromatic
- Aliphatic
What are the two Aromatic side chains?
Phenylalanine and Tryptophan
What is the largest amino acid?
Tryptophan
What is the only amino acid to have sulphur in its side chain?
Cysteine
What kind of bond can the sulfur group on Cysteine form?
Disulphide bond
Name a protein that contains a disulfide bond
Insulin
What is the difference between a hydrophobic and a hydrophilic amino acid?
Hydrophobic:
- Has UNCHARGED NON-POLAR side chain
- Found in the core of a folded protein (away from water)
Hydrophilic:
- Has UNCHARGED POLAR side chain
- Found on the surface of a folded protein (near water)
What two amino acids are Acidic?
Aspartate and Glutamate
What three amino acids are Basic?
Lysine, Arginine and Histidine
How are amino acids linked to form proteins?
- By peptide bonds
- Through a condensation reaction which results in a loss of water
Which direction does a POLYPEPTIDE chain run?
From the Amino end to the Carboxyl end
(N-terminal to C-terminal)
